CN114816137A

CN114816137A - Panel for capacitive detection, touch processing device and system and method thereof

Info

Publication number: CN114816137A
Application number: CN202210066340.9A
Authority: CN
Inventors: 叶尚泰; 张钦富
Original assignee: Egalax Empia Technology Inc
Current assignee: Egalax Empia Technology Inc
Priority date: 2021-01-20
Filing date: 2022-01-20
Publication date: 2022-07-29
Also published as: US20220229518A1; TWI811962B; US12026345B2; US11669214B2; TW202230100A; US20230259241A1

Abstract

The invention discloses a touch panel, a touch processing device, a touch system and a method for capacitive detection. The touch panel sequentially comprises: a conductive layer; an insulating layer; and at least one touch electrode layer including a plurality of first electrodes parallel to the first axis and a plurality of second electrodes parallel to the second axis, the plurality of first electrodes and the plurality of second electrodes being respectively connected to a touch processing device, wherein the touch processing device detects an external object approaching or contacting the touch panel by means of the plurality of first electrodes and the plurality of second electrodes, wherein the conductive layer is closer to the external object than the at least one touch electrode layer. The invention has the advantages of reducing or avoiding the error of electrostatic charge on capacitive detection and increasing the detection accuracy.

Description

Panel for capacitive detection, touch processing device and system and method thereof

Technical Field

The present disclosure relates to a touch panel, and more particularly, to a touch panel having a conductive layer.

Background

Touch screens or panels are one of the common input/output interfaces of modern electronic systems. When a stylus, an electronic board eraser, a hand, or clothes rub back and forth on the touch panel or the screen for a long time, electrostatic charges are generated on the surface of the touch panel or the screen. These static charges are conducted along the touch electrode to the ground. Especially in dry environments, static charges are not easily introduced into the atmosphere with moisture in the air. However, in the conducting process, if the touch processing apparatus is performing sensing, no matter using self capacitance or mutual capacitance sensing principle, the static charge may affect the elements inside the sensing circuit, so that the position shift is generated according to the sensing result. In the most severe case, the capacitance of the sampling circuit in the sensing circuit may be saturated due to the electrostatic charge, so that the sensing circuit cannot sense a finger, a stylus or other objects. Therefore, the present application is directed to avoiding or reducing the influence of electrostatic charges on capacitive touch detection.

Disclosure of Invention

According to an embodiment of the present application, a touch panel is provided, which sequentially includes: a conductive layer; an insulating layer; and at least one touch electrode layer including a plurality of first electrodes parallel to the first axis and a plurality of second electrodes parallel to the second axis, the plurality of first electrodes and the plurality of second electrodes being respectively connected to a touch processing device, wherein the touch processing device detects an external object approaching or contacting the touch panel by means of the plurality of first electrodes and the plurality of second electrodes, wherein the conductive layer is closer to the external object than the at least one touch electrode layer.

Preferably, in order to be suitable for a very dry environment, the touch panel further includes a protection layer, a second conductive layer and a second insulating layer in sequence, wherein the second insulating layer is located between the second conductive layer and the conductive layer.

Preferably, the insulating layer has a resistance value (sheet resistance) falling within 10 in order to provide a high-resistance conductive layer ⁹ To 10 ¹¹ Between ohms per square. The second insulating layer has a resistance value (sheet resistance) of 10 ⁹ To 10 ¹¹ Between ohms per square.

Preferably, in order to reduce leakage current when capacitive detection is not performed, the conductive layer is connected to the touch processing device by one or more conductive lines, and the touch processing device selectively connects the conductive layer to a direct current potential or allows the conductive layer to float in potential. The second conductive layer is connected to the touch processing device through more than one wire, and the touch processing device selectively connects the second conductive layer to a direct current potential or enables the second conductive layer to float in potential.

Preferably, in order to provide a touch screen capable of reducing electrostatic influence, the touch panel further comprises a protective layer on the conductive layer, wherein the touch panel is a part of a display device, the at least one touch electrode layer is embedded (in-cell) to the display device, wherein the insulating layer comprises an optically transparent double-sided tape, and the conductive layer and the at least one touch electrode layer are transparent.

Preferably, in order to provide a touch screen capable of reducing electrostatic influence, the touch panel further includes a display device under the at least one touch electrode layer, wherein the insulating layer includes an optically transparent double-sided tape, and the conductive layer and the at least one touch electrode layer are transparent.

Preferably, in order to provide a flexible or curved design for reducing the electrostatic influence, the conductive layer, the insulating layer and the at least one touch electrode layer have one of the following characteristics: is flexible; and curved.

According to an embodiment of the present disclosure, a capacitive detection method is provided, which is suitable for a touch panel sequentially including a conductive layer, an insulating layer, and at least one touch electrode layer including a plurality of first electrodes parallel to a first axis and a plurality of second electrodes parallel to a second axis, wherein the capacitive detection method sequentially and repeatedly performs the following steps: connecting the conductive layer to a dc potential; performing capacitive detection by using the first electrodes and the second electrodes to approach and contact an external object of the touch panel, wherein the conductive layer is closer to the external object than the at least one touch electrode layer; setting the conductive layer to a floating potential; and pausing for a period of time during which no capacitive detection is performed.

Preferably, in order to be suitable for a very dry environment, the touch panel further includes a protective layer, a second conductive layer, and a second insulating layer in sequence, the second insulating layer being located between the second conductive layer and the conductive layer, wherein the step of connecting the conductive layer to a dc potential further includes connecting the second conductive layer to a dc potential, and the step of setting the conductive layer to a floating potential further includes setting the second conductive layer to a floating potential.

According to an embodiment of the present application, a touch processing device for capacitive detection is provided, which is suitable for a touch panel, the touch panel sequentially includes a conductive layer, an insulating layer and at least one touch electrode layer, the at least one touch electrode layer includes a plurality of first electrodes parallel to a first axis and a plurality of second electrodes parallel to a second axis, wherein the touch processing device includes: a connection network for connecting the conductive layer, the plurality of first electrodes and the plurality of second electrodes, respectively; a drive circuit for connecting the connection network; a sensing circuit for connecting to the connection network; a processor for executing a plurality of instructions stored in the non-volatile memory to sequentially and repeatedly implement: connecting the conductive layer to a dc potential by the connecting network; enabling the driving circuit, the sensing circuit and the connecting network to perform capacitive detection by using the first electrodes and the second electrodes to approach and contact an external object of the touch panel, wherein the conductive layer is closer to the external object than the at least one touch electrode layer; setting the conductive layer to a floating potential by the connection network; and pausing for a period of time during which no capacitive detection is performed.

Preferably, in order to be suitable for a very dry environment, the touch panel further comprises a protection layer, a second conductive layer and a second insulating layer in sequence, the second insulating layer is located between the second conductive layer and the conductive layer, the connection network is connected to the second conductive layer, wherein the processor is further configured to: connecting the second conductive layer to a dc potential by the connecting network while connecting the conductive layer to the dc potential by the connecting network; and when the conductive layer is set to a floating potential by the connection network, setting the second conductive layer to a floating potential by the connection network.

According to an embodiment of the present application, a touch system for capacitive detection is provided, which includes the touch processing device and the touch panel as described above.

The touch system, the touch processing device and the touch processing method for capacitive detection are suitable for a touch panel with a high-impedance conductive layer. The conductive layer of the touch panel can disperse static charges accumulated on the surface of the touch panel portion to the rest of the touch panel as soon as possible. When an external object approaches or contacts the surface where static charges are accumulated, the error of the capacitive detection caused by the static charges can be reduced or avoided, and the detection accuracy is increased.

Drawings

Fig. 1 is a block diagram of a touch system according to an embodiment of the present application.

Fig. 2 is a schematic diagram of a touch screen according to an embodiment of the present application.

Fig. 3 is a schematic cross-sectional view of a touch panel according to an embodiment of the invention.

Fig. 4 is a schematic cross-sectional view of a touch panel according to another embodiment of the invention.

Fig. 5 is a schematic cross-sectional view of a touch panel according to a further embodiment of the invention.

Fig. 6 is a schematic cross-sectional view of a touch panel according to an embodiment of the invention.

Fig. 7 is a schematic diagram of a detection result according to an embodiment of the present application.

Fig. 8 is a flowchart illustrating a capacitive detection method according to an embodiment of the present disclosure.

[ description of main element symbols ]

100 touch system

110 touch processing device

111 connection Network (Interconnection Network) module

112 drive circuit module

113 sense circuit module

114 processor module

115 interface module

120 touch panel or screen

121 the first electrode

121A to 121C a first electrode

122 second electrode

122A to 122H, a second electrode

130 touch control pen

135 touch control blackboard eraser

140 host

141 input/output interface module

142 central processing unit module

143 graphic processor Module

144 memory module

145 network interface module

146 memory module

200 touch electrode layer

310 glass or protective layer

320 protective film

330 conductive layer

420 protective film

430 conductive layer

520 protective film

530 conductive layer

710 touch position

720 influence Range

800 capacitive detection method

Detailed Description

Fig. 1 is a block diagram of a touch system 100 according to an embodiment of the invention. The touch system 100 can be a conventional desktop, laptop, tablet personal computer, industrial control computer, smart phone, or other form of computer system with touch functionality.

The touch system 100 can include a touch processing device 110, a touch panel or screen 120 connected to the touch processing device, and a host 140 connected to the touch processing device. The touch system 100 can further include one or more stylus 130 and/or touchpad 135. Hereinafter, the touch panel or the screen 120 may be generically referred to as the touch screen 120 in the present application, but in the embodiment lacking a display function, a person skilled in the art can know that the touch screen referred to in the present application is a touch panel.

The touch screen 120 includes a plurality of first electrodes 121 parallel to a first axis and a plurality of second electrodes 122 parallel to a second axis. The first electrode 121 may be interleaved with a plurality of second electrodes 122 to form a plurality of sensing points or sensing regions. Likewise, the second electrodes 122 may be interleaved with the plurality of first electrodes 121 to form a plurality of sensing points or sensing regions. In some embodiments, the first electrode 121 may be referred to as a first touch electrode 121, and the second electrode 122 may also be referred to as a second touch electrode 122. The first electrode 121 and the second electrode 122 are also referred to as touch electrodes. In some embodiments of the touch screen 120, the first electrode 121 and the second electrode 122 are made of transparent materials. The first electrode 121 and the second electrode 122 may be in the same electrode layer, and conductive sheets of each first electrode 121 or second electrode 122 are connected by using a bridge-crossing manner. The first electrode 121 and the second electrode 122 can also be different electrode layers stacked on top of each other. Unless otherwise specified, the present application may be generally applicable to embodiments having a single layer or multiple electrode layers. The first axis and the second axis are generally perpendicular to each other, but the present application does not limit that the first axis is necessarily perpendicular to the second axis. In one embodiment, the first axis can be a horizontal axis or an update axis of the touch screen 120.

The touch processing device 110 may include the following hardware circuit modules: a connection Network (Interconnection Network) module 111, a drive circuit module 112, a sense circuit module 113, a processor module 114, and an interface module 115. The touch processing device 110 can be implemented in a single integrated circuit, which can include one or more chips. The touch processing device 110 can also be implemented by using a plurality of integrated circuits and an interconnection circuit board carrying the plurality of integrated circuits. The touch processing device 110 may also be implemented in the same integrated circuit as the host 140, or may be implemented in the same chip as the host 140. In other words, the present application is not limited to the embodiment of the touch processing device 110.

The connection network module 111 is used for respectively connecting the plurality of first electrodes 121 and/or the plurality of second electrodes 122 of the touch screen 120. The connection network module 111 can receive the control command from the processor module 114, and is used to connect the driving circuit module 112 and any one or more touch electrodes, and also used to connect the sensing circuit module 113 and any one or more touch electrodes. The connection network module 111 may include a combination of one or more Multiplexers (MUXs) to implement the above-described functions.

The driving circuit module 112 may include a clock generator, a frequency divider, a frequency multiplier, a phase-locked loop, a power amplifier, a dc-dc voltage converter, a rectifier and/or a filter, and the like, and is configured to provide a driving signal to any one or more touch electrodes through the connection network module 111 according to a control command of the processor module 114. Various types of analog or digital signal modulation may be performed on the driving signals to transmit certain information. The Modulation method includes, but is not limited to, Frequency Modulation (FM), Phase Modulation (Phase Modulation), Amplitude Modulation (AM), double Sideband Modulation (DSB), single Sideband Modulation (SSB-AM), Vestigial Sideband Modulation (Vestigial Sideband Modulation), amplitude shift Modulation (ASK), Phase shift Modulation (PSK), Quadrature Amplitude Modulation (QAM), frequency shift Modulation (FSK), Continuous Phase Modulation (CPM), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiplexing (OFDM), and Pulse Width Modulation (PWM). The driving signal may comprise one or more square waves, sinusoidal waves, or any modulated waveform. The driving circuit module 112 may include one or more channels, and each channel may be connected to any one or more touch electrodes through the connection network module 111.

The sensing circuit module 113 may include an integrator, a sampler, a clock generator, a frequency divider, a frequency multiplier, a phase-locked loop, a power amplifier, an operational amplifier, a multiplier, a dc-dc voltage converter, a rectifier and/or a filter, and the like, and is configured to sense any one or more touch electrodes through the connection network module 111 according to a control command of the processor module 114. When the touch signal is transmitted through one of the touch electrodes, the other touch electrode can sense the touch signal. The sensing circuit module 113 can perform corresponding demodulation on the driving signal sensed by the other touch electrode in accordance with the modulation method executed by the driving circuit module 112, so as to recover the information carried by the driving signal. The sensing circuit module 113 may include one or more channels, and each channel may be connected to any one or more touch electrodes through the connection network module 111. Each channel may be sensed and demodulated at the same time.

In one embodiment, the driving circuit module 112 and the sensing circuit module 113 may include an analog front-end (AFE) circuit. In another embodiment, the driving circuit module 112 and the sensing circuit module 113 may include a digital back-end (DBE) circuit in addition to the analog front-end circuit. While the driving circuit module 112 and the sensing circuit module 113 only include analog front-end circuits, digital back-end circuits can be implemented in the processor module 114.

The processor module 114 may include a digital signal processor, which is used to connect the analog front-end circuits of the driving circuit module 112 and the sensing circuit module 113, respectively, or connect the digital back-end circuits of the driving circuit module 112 and the sensing circuit module 113, respectively. The processor module 114 may include an embedded processor, non-volatile memory, and volatile memory. The non-volatile memory may store a common operating system or real-time operating system, and applications that execute under the operating system. The aforementioned operating system and application program include a plurality of instructions and data, and after the processor (including embedded processor and/or digital signal processor) executes the instructions, the instructions can be used to control other modules of the touch processing device 110, including the connection network module 111, the driving circuit module 112, the sensing circuit module 113 and the interface module 115. For example, the processor module 114 may include the 8051 family of processors commonly used in the industry, the Intel (Intel) i960 family of processors, the ARM (ARM) Cortex-M family of processors, and the like. The present application does not limit the type and number of processors included in the processor module 114.

The instructions and data may be used to implement the steps described herein, as well as processes and methods comprising such steps. Some instructions may operate independently within the processor module 114, such as arithmetic and logic operations (arithmetric and logic operations). Other instructions may be used to control other modules of the touch processing device 110, which may include an input/output interface of the processor module 114 to control other modules. Other modules may also provide information to the operating system and/or applications executed by the processor module 114 via the I/O interface of the processor module 114. It will be understood by those of ordinary skill in the art that the present invention may be implemented using any of the modules and instructions described above, given the general knowledge of computer architecture and architecture.

The interface module 115 may include various serial or parallel buses, such as Universal Serial Bus (USB), integrated circuit bus (I) ² C) And an input/output interface of an industrial standard such as Peripheral Component Interconnect (PCI), peripheral component interconnect Express (PCI-Express), IEEE 1394, or the like. The touch processing device 110 is connected to the host 140 through an interface module 115.

The touch system 100 can include one or more styli 130 and/or trackpads 135. The stylus 130 or the touchpad 135 may be an emitter that emits an electrical signal, and may include an active emitter that actively emits an electrical signal, a passive emitter that passively emits an electrical signal, or a reactive emitter that emits an electrical signal in response to an external electrical signal. The stylus 130 or the touchpad 135 may comprise one or more electrodes for synchronously or asynchronously receiving electrical signals from the touchscreen 120 or for synchronously or asynchronously sending electrical signals to the touchscreen 120. The electrical signals may employ one or more of the modulation schemes described above.

The stylus 130 or the touchpad 135 may be a conductor for conducting a driving signal or grounding through the user's hand or body. The stylus 130 or the touchpad 135 can be connected to the input/output interface module 141 of the host 140 or other modules below the input/output interface module 141 in a wired or wireless manner.

The touch processing device 110 can detect one or more external conductive objects, such as a finger or a palm of a human body or a passive stylus 130 or a touchpad 135, and can also detect a stylus 130 or a touchpad 135 that emits an electrical signal, via the touch screen 120. The touch processing device 110 may use a mutual-capacitance (mutual-capacitance) or self-capacitance (self-capacitance) method to detect an external conductive object. The stylus 130, the touchpad 135, and the touch processing device 110 may use the signal modulation and the corresponding signal demodulation to transmit information by using electrical signals. The touch processing device 110 can utilize the electrical signal to detect information such as one or more of a proximity position where the stylus 130 or the touchpad 135 is close to or in contact with the touchscreen 120, a sensor status (e.g., a pressure sensor or a button) on the stylus 130 or the touchpad 135, a pointing direction of the stylus 130 or the touchpad 135, or a tilt angle of the stylus 130 or the touchpad 135 relative to a plane of the touchscreen 120.

The host 140 is a main device for controlling the touch system 110, and may include an input/output interface module 141 connected to the interface module 115, a central processor module 142, a graphics processor module 143, a memory module 144 connected to the central processor module 142, a network interface module 145 connected to the input/output interface module 141, and a memory module 146.

The memory module 146 includes a non-volatile memory, such as a hard disk, electrically erasable programmable read-only memory (EEPROM), or flash memory. The memory module 146 can store a general operating system and applications executed under the operating system. The network interface module 145 may include a hardware network connection interface for wired and/or wireless connections. The network interface module 145 may conform to common industry standards such as IEEE 802.11 wireless area network standards, IEEE 802.3 wired area network standards, 3G, 4G, and/or 5G wireless communication network standards, bluetooth wireless communication network standards, and the like.

The cpu module 142 may be directly or indirectly connected to the io interface module 141, the graphics processor module 143, the memory module 144, the network interface module 145, and the memory module 146. The central processor module 142 may contain one or more processors or processor cores. Conventional processors may include processors of the Intel, or Intel, or the Amplifier, Intel, or the like, or may include processors of the Complex Instruction Set (CISC) or Reduced Instruction Set (RISC). The operating system and the application programs include a plurality of instructions and data corresponding to the instruction set, and the instructions are executed by the cpu module 142 and then used to control other modules of the touch system 100.

The optional graphics processor module 143 is typically a part of the computation used to process graphics output related data. The graphics processor module 143 can be coupled to the touchscreen 120 described above for controlling the output of the touchscreen 120. In some applications, the host 140 may not require specialized processing by the graphics processor module 143, and may directly cause the CPU module 142 to perform the graphics output related computing components.

The host 140 may also include other components or elements not shown in fig. 1, such as a sound input/output interface, a keyboard input interface, a mouse input interface, a track ball input interface, and/or other hardware modules. It should be understood that the touch system 100 is only illustrative and that the rest of the features related to the invention provided in the present application need to be referred to in the specification and claims.

Please refer to fig. 2, which is a schematic diagram of a touch screen according to an embodiment of the present application. For convenience of illustration, the touch screen 120 only includes three first electrodes 121, which are the

first electrodes

121A, 121B, and 121C in sequence. The touch screen 120 includes a plurality of second electrodes 122A to 122H.

In the mutual capacitance detection mode, the driving circuit module 112 provides a driving signal to one of the three first electrodes 121 in a time-sharing manner. When the driving signal is provided, the sensing circuit module 113 performs three sensing operations on all the second electrodes 122 simultaneously, so as to obtain three sets of sensing information of the one-dimensional array. Each set of one-dimensional arrays includes sensing results for each of the second electrodes 122. The three sets of one-dimensional sensing information can form a two-dimensional array of sensing information or sensing images according to the sequence of the corresponding first electrodes 121 emitting driving signals. Using the two-dimensional array or sensed image, the processor module 114 can detect whether an external conductive object is proximate to the touch screen 120.

In one embodiment, the sensing circuit module 113 outputs a sensing result corresponding to each of the second electrodes 122. In another embodiment, the sensing circuit module 113 outputs a difference between the sensing results of two adjacent second electrodes 122. Each element of the one-dimensional array is a difference value. Since the interference is usually of a regional nature. The interfering signals for two adjacent signals do not typically differ too much. Therefore, the difference between the sensing results of two adjacent second electrodes 122 can eliminate most of the sensing values caused by the interference signals.

In a further embodiment, the sensing circuit module 113 outputs two difference values of the sensing results of the adjacent three second electrodes 122. For example, a first difference between the sensing signals of the second electrode 122B and the second electrode 122A can be calculated, and then a second difference between the sensing signals of the second electrode 122C and the second electrode 122B can be calculated. Each element of the one-dimensional array is a double difference value. As such, interference is typically regional in nature. The interfering signals for two adjacent signals do not typically differ too much. Therefore, the sensing values caused by most of the interference signals can be eliminated by using the double difference of the sensing results of the adjacent three second electrodes 122. The sensing information, the difference value or the double difference value is used as a two-dimensional array or a sensing image formed by the sensing information, so that a sensing result with stronger anti-interference function can be obtained.

Fig. 3 is a schematic cross-sectional view of a touch panel according to an embodiment of the invention. In fig. 3, the touch panel 120 is shown, but a touch screen can be formed by adding a display below the touch panel 120. In addition, although the touch panel 120 in the embodiments shown in fig. 3 to 6 is a flat surface, the present application can be applied to a curved touch panel or a screen 120, and can also be applied to a flexible touch panel or a screen 120.

The lowermost layer of the touch panel 120 is a touch electrode layer 200. As described above, the touch electrode layer 200 may include one or more layers. The first electrode 121 and the second electrode 122 may be located in one or more layers of the touch electrode layer 200. Above the touch electrode layer 200 is a glass layer or protective layer 310 for protecting the touch electrode layer 200 and the display below.

Above the glass layer or protective layer 310 is a high resistance conductive layer 330. The glass layer or the protection layer 310 also plays a role of insulation for insulating the touch electrode layer 200 and the conductive layer 330. A protective film 320 is also provided over the conductive layer 330. The upper surface of the protective film 320 has abrasion resistance and wear resistance. For example, the protection film 320 may be made of Polyethylene (PE). The protective film 320 is made of a nonconductive material. The high-resistance conductive layer 330 may be a conductive film made of polyacrylic (acrylic). The resistance value (sheet resistance) of which may fall within 10 ⁹ Ohm to 10 ¹¹ Between ohms. In an embodiment, the touch electrode layer 200, the passivation layer 310, the conductive layer 330 and the protective film 320 may be transparent or flexible. However, the touch electrode layer 200, the passivation layer 310, the conductive layer 330 and the protective film 320 are not limited to be transparent or flexible.

The high impedance conductive layer 330 may be floating, grounded, or connected to a dc potential. In one embodiment, the conductive layer 330 can be connected to a special processing circuit of the touch processing device 110 by one or more wires. In one example, the conductive layer 330 can be connected to the connection network module 111 of the touch processing device 110 by one or more wires. Since the conductive layer 330 has a high impedance value, electric lines of force of the capacitance between the first electrode 121 and the second electrode 122 can penetrate through the protection layer 310, the conductive layer 330 and the protection film 320. When the power line of the capacitor is affected by a finger, the stylus 130 or the touchpad 135, the touch processing device 110 can detect the change of the capacitor. When static charges are accumulated on the upper surface of the touch panel 120 due to friction of a finger, the stylus 130, or the touchpad 135, the static charges are dispersed elsewhere through the conductive layer 330, and the interference intensity of the contact portion is reduced. Particularly, when the touch processing device 110 uses the difference value or the double difference value to detect the touch event, the interference can be further reduced.

Fig. 4 is a schematic cross-sectional view of a touch panel according to another embodiment of the invention. In contrast to the touch panel 120 shown in fig. 3, the conductive layer 430 with high impedance and the protective film 420 are sandwiched between the glass layer or protective layer 310 and the touch electrode layer 200. The protective film 420 is used to isolate the conductive layer 430 from the touch electrode layer 200. In one embodiment, the protective film 420 may be an insulating tape. When the touch panel 120 is transparent, the protection film 420 may be an optically clear adhesive tape (OCA).

Since the glass layer or the protection layer 310 has better abrasion resistance than the protection film 320, the embodiment of fig. 4 can make the touch panel 120 more abrasion resistant and have stronger protection capability than the embodiment of fig. 3.

Fig. 5 is a schematic cross-sectional view of a touch panel according to a further embodiment of the invention. The touch panel 120 structure of fig. 5 further omits the glass layer or the protective layer 310. Above the touch electrode layer 200 are a high-impedance conductive layer 530 and a protective film 520 in sequence. Since the touch electrode layer 200 may also have a non-conductive base material or substrate, the touch electrode layer 200 and the high-resistance conductive layer 530 may be isolated as long as the non-conductive base material or substrate is located between the first electrode 121 or the second electrode 122 and the high-resistance conductive layer 530.

Fig. 6 is a schematic cross-sectional view of a touch panel according to an embodiment of the invention. The structure of the touch panel shown in fig. 6 includes the high-impedance

conductive layers

330 and 430 and the

protective films

320 and 420 of fig. 3 and 4. The embodiment shown in fig. 6 is particularly suitable for very dry areas, where the electrostatic effect is removed as soon as possible by using the dual high-impedance

conductive layers

330 and 430.

In a variation of the embodiment shown in fig. 6, the impedance coefficients of the conductive layer 330 and the conductive layer 430 may be the same. In another variation, however, the impedance coefficients of the conductive layer 330 and the conductive layer 430 may be different. In a variation of the embodiment shown in fig. 6, the conductive layer 330 and the conductive layer 430 may be connected to the same ground potential or the same dc potential. In another variation, however, the conductive layer 330 and the conductive layer 430 may be connected to different dc potentials. The potentials of the high-impedance conductive layer 330 and the conductive layer 430 can be floating, grounded, or connected to a dc potential. In one embodiment, the

conductive layers

330 and 430 can be connected to the special processing circuit of the touch processing device 110 by one or more wires. In one example, the conductive layer 330 and the conductive layer 430 can be connected to the connection network module 111 of the touch processing device 110 by one or more wires, respectively.

Since the sensing circuit module 113 in the touch processing device 110 includes the sampling circuit, when a large amount of static charges are introduced into the sensing circuit module 113, the sampling circuit may not only be saturated, but also the sensing circuit module 113 may be damaged. Therefore, the embodiments shown in fig. 3 to 6 can protect the sensing circuit module 113 from possible damage caused by static charges.

Please refer to fig. 7, which is a schematic diagram illustrating a detection result according to an embodiment of the present application. In fig. 7, if a conductive layer with higher impedance is used to cover the touch electrode layer 200, the touch processing device 110 can obtain the finger touch position 710 more clearly. Since the affected part of the capacitance value is approximately located near the overlapping area of the first electrode 121B and the second electrode 122F, the range is not too large, which is equivalent to the area covered by the finger on the touch panel or the screen 120. However, if a conductive layer with lower impedance is used, the affected part of the capacitance is enlarged, and the area size of the affected area 720 may be equal to the area size of the touch panel or the screen 120 covered by the object with the palm size. The shape of the influence range 720 is not necessarily equivalent to the shape of the palm. Therefore, it is also one of the features of the present application to select a conductive layer with higher appropriate impedance to be disposed on the touch electrode layer 200 to avoid the touch of fingers being regarded as the touch of palm or other large objects.

Please refer to fig. 8, which is a flowchart illustrating a capacitive detection method 800 according to an embodiment of the present application. The capacitive detection method 800 can be applied to the touch processing device 110 of fig. 1. In one embodiment, the processor module 114 may execute a plurality of instructions stored in a non-volatile memory to implement the capacitive detection method 800. The capacitive detection method 800 can begin at step 810.

Step 810: the high-impedance conductive layer is connected to a direct current potential. In one embodiment, the dc potential may be a ground potential. When applied to the embodiment of fig. 6, at least one of the high-impedance conductive layer 330 and the conductive layer 430 is connected to a dc potential. In one embodiment, the touch processing device 110 may include circuitry dedicated to performing the step 810 according to the commands of the processor module 114. In another embodiment, the connection network module 111 of the touch processing device 110 can connect the conductive layer to the dc potential according to the command of the processor module 114. After this step, the static charges accumulated on the surface of the touch panel or the screen 120 are guided to the ground or distributed evenly on the touch panel or the screen 120.

Step 820: capacitive detection is performed by using a plurality of touch electrodes under the high-impedance conductive layer. The capacitive detection at this step can be self-capacitance detection or mutual capacitance detection, which is well known to those skilled in the art, so as to detect an external object approaching or touching the touch panel or the screen 120.

Step 830: the conductive layer with high impedance is set to a floating potential. So as to reduce the leakage current flowing from the high-impedance conductive layer to the ground via an external object (such as a human body) for reducing power consumption.

Step 840: the capacitive detection is stopped. During this step, the capacitive detection may be suspended, and after a period of time, the process returns to step 810.

According to an embodiment of the present application, a touch panel is provided, sequentially comprising: a conductive layer; an insulating layer; and at least one touch electrode layer including a plurality of first electrodes parallel to the first axis and a plurality of second electrodes parallel to the second axis, the plurality of first electrodes and the plurality of second electrodes being respectively connected to a touch processing device, wherein the touch processing device detects an external object approaching or contacting the touch panel by means of the plurality of first electrodes and the plurality of second electrodes, wherein the conductive layer is closer to the external object than the at least one touch electrode layer.

Preferably, in order to provide a touch screen capable of reducing electrostatic influence, the touch panel further comprises a display device under the at least one touch electrode layer, wherein the insulating layer comprises an optically transparent double-sided tape, and the conductive layer and the at least one touch electrode layer are transparent.

According to an embodiment of the present application, a touch processing device for capacitive detection is provided, which is suitable for a touch panel, the touch panel sequentially includes a conductive layer, an insulating layer and at least one touch electrode layer, the at least one touch electrode layer includes a plurality of first electrodes parallel to a first axis and a plurality of second electrodes parallel to a second axis, wherein the touch processing device includes: a connection network for connecting the conductive layer, the plurality of first electrodes and the plurality of second electrodes, respectively; a drive circuit for connecting the connection network; a sensing circuit for connecting to the connection network; a processor for executing a plurality of instructions stored in the non-volatile memory to sequentially and repeatedly implement: connecting the conductive layer to a dc potential by the connecting network; enabling the driving circuit, the sensing circuit and the connection network to perform capacitive detection by using the first electrodes and the second electrodes to approach and contact an external object of the touch panel, wherein the conductive layer is closer to the external object than the at least one touch electrode layer; setting the conductive layer to a floating potential by the connection network; and pausing for a period of time during which no capacitive detection is performed.

The touch system, the touch processing device and the touch processing method for capacitive detection are suitable for a touch panel with a high-impedance conductive layer. The conductive layer of the touch panel can disperse static charges accumulated on the surface of the touch panel portion to the rest of the touch panel as soon as possible. When an external object approaches or contacts a surface where static charges are accumulated, errors caused by the static charges on capacitive detection can be reduced or avoided, and the detection accuracy is improved.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A touch panel, comprising in order:

a conductive layer;

an insulating layer; and

at least one touch electrode layer including a plurality of first electrodes parallel to a first axis and a plurality of second electrodes parallel to a second axis, the plurality of first electrodes and the plurality of second electrodes being respectively connected to a touch processing device, wherein the touch processing device detects an external object approaching or contacting the touch panel by the plurality of first electrodes and the plurality of second electrodes,

wherein the conductive layer is closer to the external object than the at least one touch electrode layer.

2. The touch panel of claim 1, further comprising a passivation layer, a second conductive layer and a second insulating layer in sequence, wherein the second insulating layer is located between the second conductive layer and the conductive layer.

3. The touch panel of claim 1, wherein the insulating layer has a resistance value between 109 and 1011 ohms per square.

4. The touch panel of claim 2, wherein the second insulating layer has a resistance value between 109 and 1011 ohms per square.

5. The touch panel of claim 1, wherein the conductive layer is connected to the touch processing device by more than one wire, and the touch processing device selectively connects the conductive layer to a DC potential or allows the conductive layer to float.

6. The touch panel of claim 2, wherein the second conductive layer is connected to the touch processing device by more than one wire, and the touch processing device selectively connects the second conductive layer to a DC potential or allows the second conductive layer to float.

7. The touch panel of claim 1, further comprising a protective layer over the conductive layer, wherein the touch panel is part of a display device, wherein the at least one touch electrode layer is embedded in the display device, wherein the insulating layer comprises an optically transparent double-sided tape, and wherein the conductive layer and the at least one touch electrode layer are transparent.

8. The touch panel according to one of claims 1 to 6, further comprising a display device under the at least one touch electrode layer, wherein the insulating layer comprises an optically transparent double-sided tape, and the conductive layer and the at least one touch electrode layer are transparent.

9. The touch panel of any one of claims 1 to 7, wherein the conductive layer, the insulating layer and the at least one touch electrode layer have one of the following characteristics: is flexible; and curved.

10. A capacitive detection method is suitable for a touch panel, the touch panel sequentially comprises a conductive layer, an insulating layer and at least one touch electrode layer, the at least one touch electrode layer comprises a plurality of first electrodes parallel to a first axis and a plurality of second electrodes parallel to a second axis, wherein the capacitive detection method comprises the following steps of:

connecting the conductive layer to a dc potential;

performing capacitive detection by using the first electrodes and the second electrodes to approach and contact an external object of the touch panel, wherein the conductive layer is closer to the external object than the at least one touch electrode layer;

setting the conductive layer to a floating potential; and

pausing for a period of time during which no capacitive detection is performed.

11. The capacitive detection method of claim 10, wherein the touch panel further comprises a passivation layer, a second conductive layer, and a second insulating layer in sequence, the second insulating layer being between the second conductive layer and the conductive layer, wherein the step of connecting the conductive layer to a dc potential further comprises connecting the second conductive layer to a dc potential, and the step of setting the conductive layer to a floating potential further comprises setting the second conductive layer to a floating potential.

12. A touch processing device for capacitive detection, adapted to a touch panel, the touch panel sequentially comprising a conductive layer, an insulating layer and at least one touch electrode layer, the at least one touch electrode layer comprising a plurality of first electrodes parallel to a first axis and a plurality of second electrodes parallel to a second axis, wherein the touch processing device comprises:

a connection network for connecting the conductive layer, the plurality of first electrodes and the plurality of second electrodes, respectively;

a drive circuit for connecting the connection network;

a sensing circuit for connecting to the connection network;

a processor for executing a plurality of instructions stored in the non-volatile memory to sequentially and repeatedly implement:

connecting the conductive layer to a dc potential by the connecting network;

enabling the driving circuit, the sensing circuit and the connection network to perform capacitive detection by using the first electrodes and the second electrodes to approach and contact an external object of the touch panel, wherein the conductive layer is closer to the external object than the at least one touch electrode layer;

setting the conductive layer to a floating potential by the connection network; and

pausing for a period of time during which no capacitive detection is performed.

13. The touch processing apparatus of claim 12, wherein the touch panel further comprises a passivation layer, a second conductive layer, and a second insulating layer in sequence, the second insulating layer being between the second conductive layer and the conductive layer, the connection network being connected to the second conductive layer, wherein the processor is further configured to:

connecting the second conductive layer to a dc potential by the connecting network while connecting the conductive layer to the dc potential by the connecting network; and

when the conductive layer is set to a floating potential by the connection network, the second conductive layer is set to a floating potential by the connection network.

14. A touch system for capacitive detection, comprising the touch processing device and the touch panel according to claim 12 or 13.